The present invention relates to a control device for a printer which can print out format data and printing data in a superposed state, and more particularly to an improvement in positioning on printing paper between format data and printing data.
In a printer control device of format overlay type, format data read out of a memory is combined with printing data, and then sent to a printer to print the combined data at the same time. Accordingly, the above printer control device does not require that an operator replace printing paper in accordance with a desired format, though such a requirement is unavoidable in a method of printing variable information on printing paper, on which a format made up of ruled lines and characters is previously printed. These are described in U.S. Pat. No. 4,125,829.
FIG. 1 shows an example of documents to be printed. In FIG. 1, each of hatched areas indicates a printing area where printing data is printed, and the remaining area indicates a format. In general, several kinds of formats are stored in a memory, and one of the formats is selectively read out of the memory to be combined with the printing data.
In such a conventional printer control device of the format overlay type, line feed processing, column positioning processing and other types of processing have to be closely specified by a user program, in order to fit the printing position of the printing data to the format. For example, it has to be determined by a user program which line from the top of the document in FIG. 1 is selected and which character position from the left end of the selected line is used as the printing position for printing data indicating a "month". The printing position of printing data indicating a "year" is specified in the same manner as above, and so on. Further, it is required to alter programs each time the format of the document is changed.